SSL devices generally use semiconductor light emitting diodes (“LEDs”), organic light emitting diodes (“OLEDs”), laser diodes (“LDs”), and/or polymer light emitting diodes (“PLEDs”) as sources of illumination rather than electrical filaments, a plasma, or a gas. FIG. 1 is a cross-sectional diagram of a portion of a conventional indium-gallium nitride (“InGaN”) LED die 10. As shown in FIG. 1, the LED die 10 includes a substrate 12 (e.g., silicon carbide, sapphire, or silicon), an N-type gallium nitride (“GaN”) material 14, an active region 16 (e.g., GaN/InGaN multi quantum wells (“MQWs”)), and a P-type GaN material 18 on top of one another in series. The LED die 10 can also include a first contact 11 on the P-type GaN material 18 and a second contact 15 on the N-type GaN material 14.
The GaN/InGaN materials of the LED die 10 are generally formed via epitaxial growth and typically include a large number of crystal defects that can negatively impact the optical and/or electrical performance of the LED die 10. For example, FIG. 2 is a transmission electron microscopy (“TEM”) image 20 of a GaN layer 24 formed on a sapphire substrate 22 via metal organic chemical vapor deposition (“MOCVD”). As shown in FIG. 2, the GaN layer 24 includes a plurality of threading dislocations 26 extending away from the substrate 22 into the GaN layer 24. It is believed that the threading dislocations 26 and/or other crystal defects can negatively impact the performance of LEDs. Accordingly, several improvements to reduce the negative impact of crystal defects in LEDs may be desirable.